Mooring structure in combination with a fender

ABSTRACT

A mooring structure in combination with a fender, the mooring structure comprising a fixed element supporting a rotatable head having first and second relatively rotatable parts, a weight structure supported by a plurality of pairs of ropes, the ropes of each pair being respectively connected to the first and second parts so that relative rotation of the parts lifts the weight structure by increasing the angle between the ropes of each pair to provide an increasing restoring force, movement of the fender causing such relative rotation of the parts and adjustment means for adjusting the effective lengths of the ropes to adjust the device to form a &#39;&#39;soft&#39;&#39; fender or a &#39;&#39;hard&#39;&#39; fender.

United States Patent Kohring [451 July 11, 1972 [54] MOORING STRUCTURE IN COMBINATION WITH A FENDER Walter Kohrlng, Angle View, Pilgrim's Way, West Humble, Dorking. Surrey. England [22] Filed: March 18; [97] [2|] Appl. No.: 125,645

[72] Inventor:

3.4043554 lO/l968 Kohring ..ll4/23O Priman' Examiner-Trygve M. Blix Attorney-Jar] W. Flocks ABSTRACT A mooring structure in combination with a fender. the mooring structure comprising a fixed element supporting a rotatable head having first and second relatively rotatable parts. a weight structure supported by a plurality of pairs of ropes, the ropes of each pair being respectively connected to the first and second parts so that relative rotation of the parts lifts the weight structure by increasing the angle between the ropes of each pair to provide an increasing restoring force. movement of the fender causing such relative rotation of the parts and adjustment means for adjusting the effective lengths of the ropes to adjust the device to form a soft fender or a hard fender.

10 Claims, 5 Drawing figures PATENTEDJUL H m2 sum 1 or 4 FIG, I 45 55 #0 U fiv 2 6 8 (I 3 8 7 5 5 I rum 2 b ll m [k F u; C

INVENTOR WALTER KOHRING- BY KARL IJ Ffacq ATTORNEY mm fi m PATENTEDJULI I ma SHEET 2 OF 4 J Qm ww mN m% 0% PATENTEDJUL H r972 3,675,610

SHEET u or 4 27 60A FIG. 4

MOORING STRUCTURE IN COMBINATION WITH A FENDER BACKGROUND OF THE INVENTION This invention relates to a structure capable of being used as a mooring and incorporating a fender which will allow a vessel to be moored alongside and will accommodate surging move ments of such a vessel.

In my US. Pat. No. 3,404,654 (particularly FIGS. 21 and 22) l have disclosed a structure capable of being used as a mono-mooring comprising a fixed element, a head connected to the fixed element having first and second parts rotatable relative to one another from a rest position about a vertical axis and a weight structure supported by a plurality of pairs of ropes, the ropes of each pair being respectively connected to the first and second parts so that relative rotation of the parts from the rest position lifts the weight structure by increasing the angle between the ropes of each pair to provide an increasing restoring force tending to move the parts back to the rest position.

The mooring structure may be attached to a fender, so that movement of the fender at least towards the structure tends to lift the weight structure.

SUMMARY OF THE INVENTION An object of the present invention is to provide an improvement to such a mooring structure which enables the strength of the restoring force to be adjusted.

Accordingly the invention provides a mooring structure comprising a fixed element, a rotatable head mounted on the fixed element and having first and second parts rotatable relative to one another from a rest position about a vertical axis, a weight structure supported by a plurality of pairs of ropes, the ropes of each pair being respectively connected to the first and second parts so that relative rotation of the parts from the rest position lifts the weight of the structure by increaing the angle between the ropes of each pair to provide an increasing restoring force tending to move the parts back to the rest position, a fender coupled to the mooring structure such that movement of the fender at least towards the mooring structure causes relative rotation of the head parts and adjustment means for adjusting the efi'ective lengths of the pairs of ropes, whereby the restoring force per angular movement of the head parts is adjusted.

BRIEF DESCRIPTION OF THE DRAWINGS One embodiment of a mooring in accordance with the invention will now be described by way of example only with reference to the accompanying drawings of which:

FIG. I is a vertical section through a form of mooring incorporating a fender;

FIG. 2 is a plan view of the mooring of FIG. I showing the mooring structure and fender with the additional winding mechanism omitted;

FIG. 3 is a plan view of the mooring showing the additional winding mechanism, with the fender and parts of the mooring structure omitted;

FIG. 4 is a view showing the axle box and weight structure with their suspension ropes, and

FIG. 5 is a section on line V V ofFlG. 4.

DETAILED DESCRIPTION Referring to FIGS. 1 and 2 the mooring comprises a hollow annular casing 1 having outer and inner walls 2 and 3, the casing being secured to a concrete base 4 secured to the seabed 5 by piles or the like. The hollow annulus 6 is extended downwardly into the base 4 and accommodates with clearance an annular weight structure 7. A central hollow pillar 8 extends upwardly from a plate 9 closing the upper end of the inner casing wall 3. The casing l and pillar 8 support a rotatable head rotatable about the vertical axis of the structure. The head 15 is formed in two parts 16 and rotatable relative to one another. The first outer part 16 runs on axial bearings 17 and radial bearings 18 and the second part 20 runs on axial bearings 21 and radial bearings 22. The parts 16 and 20 have outwardly projecting bearing amts 23 and 24 respectively which in the rest position of the structure are disposed at opposite sides of the structure with their bearing surfaces 25 in a common plane. The weight structure 7 is supported by a plurality of pairs of ropes 27, the lower ends of each pair being anchored to the weight structure at 26 and the upper end of one rope of each pair being secured to part 16 and the upper end of the other rope of each pair being secured to part 20.

A fender is secured to and supported by the mooring structure. The fender is shown at 38 having an outer vertical fender surface 39', a framework of horizontal tubes 40 and vertical tubes 41 is secured to the fender at 42 at each side of the fender to embrace the mooring. Tubes 40 are slidably supported on brackets 43 on the mooring. Supported on an upper cylindrical extension 36 of the weight structure is a further overhead framework 44 formed by two beams 45 parallel to the tubes 40 and s cm beam 46 secured thereto. A pair of forward links 47 have their upper ends pivotally attached to the front ends of the beams 45 and 48 and their lower ends pivotally attached to the fender at 49. A further pair of links 50 parallel to the links 47 have their upper ends pivotally secured at 51 to the upper ends of beam 46 and their lower ends pivotally secured at 52 to the lower tubes 40.

The links 47 and 50 thus form a parallel linkage connecting the arms carried by the fender and carried by the vertical extension 36 of the weights. Because the frame 44 moves upwards on upward movement of the vertical extension of the weights the fender will in fact move horizontally. The arms 23,24 connected to the rotatable parts are engaged by the parts 53 of the upward extension of the vertical tubes 41. Thus inward movement of the fender causes the rotatable parts to rotate relative to one another thus lifting the weights and providing a restoring force.

The rest position of the rotatable parts 16 and 20, to which they are urged by the action of the weight structure 7 is shown in full line in FIG. 2. In this position the ropes of each pair lie substantially in a common radial plane. When the ship or the like secured to the fender surges towards or away from the mooring structure, the parts I6 and 20 are rotated relative to one another as shown by the broken line positions of parts 23 and 24; this opens the angles between the ropes of each pair thus Iifiing the weight structure. During such rotation an increasing restoring force is applied by the weight structure.

The overhead framework 44 carries a drum incorporating a gear wheel 55 to be driven by a separate hydraulic pump or electric motor under the control of an operator. This drum has attached to it a plurality of auxiliary ropes 56, corresponding to the number of pairs of ropes 57 supporting the weight structure 54, in this case eight. Each rope 57 passes over a guide pulley 58 at the periphery of the platform and extends downwardly to support at its lower end an axle box 60.

Each axle box 60 is guided for vertical movement by guides 61 in the wall 2 of the main mooring structure. The guides are reinforced by bearing surfaces 63 acting in slots 64 in the axle box. Each axle box carries two guide wheels 65 which engage the ropes of the associated pair 27 substantially in a plane 66, which plane is a radial plane of the mooring.

Turning of the gear wheel 55 thus tends to wind up the ropes 56 and to raise the axle boxes 60 for example from their rest position in which they rest on the weight structure to the position shown at 60A in FIG. 4. It will be seen that in this raised position the axle boxes cause ropes 27 to be effectively shortened to increase their included angle as indicated at 27A in FIG. 4. This increases the restoring force which will be applied by the weight structure. Thus any inward push on the fender will be more strongly resisted than would be the case without the axle boxes or with axle boxes in their rest position and will provide what is termed a hard mooring. It has been found advantageous to have a hard mooring when a ship first engages the fender. However, once the ship is moored alongside and is at rest against the fender faces, experience has proved that a soft fender is desirable and this is achieved by unwinding the turning gear wheel 55 alter the ship is moored and thus providing a longer effective suspension rope to the weight system.

Pilot weights 67 are attached to the bottoms of the axle boxes by ropes extending through the weight structure to maintain taut conditions at all times.

What is claimed is:

l. A mooring structure comprising a fixed element, a rotatable head mounted on the fixed element and having first and second parts rotatable relative to one another from a rest position about a vertical axis, a weight structure supported by a plurality of pairs of ropes, the ropes of each pair being respectively connected to the first and second parts so that relative rotation of the parts from the rest position lifts the weight structure by increasing the angle between the ropes of each pair to provide an increasing restoring force tending to move the parts back to the rest position, a fender coupled to the mooring structure such that movement of the fender at least towards the mooring structure causes relative rotation of the head parts and adjustment means for adjusting the effective lengths of the pairs of ropes, whereby the restoring force per angular movement of the head parts is adjusted.

2. A mooring structure according to claim 1 in which the adjustment means includes guide members, one associated with each pair of ropes and each arranged to maintain the ropes of its pair in a substantially common radial plane at and below the level of the guide members.

3. A structure according-to claim I in which the adjustment means includes guide members in the form of axle boxes. one associated with each pair of ropes, each axle box having a pair of pulleys engaging respective ones of its pair of ropes.

4. A structure according to claim 3 in which for each axle box the edges of the pulleys engaged by the ropes lie in a substantially common radial plane.

5. A structure according to claim 2 in which the ropes of each pair are anchored at their lower ends to the weight structure in a substantially common radial plane and pass through guide members before having their upper ends respectively connected to the first and second head parts.

6. A structure according to claim 2 in which the adjustment means includes means for raising the guide members.

7. A structure according to claim 6 in which the means for raising the guide members includes a support line for each guide member, all the support lines being connected to a drum and means for rotating the drum to wind up the support lines.

8. A structure according to claim 2 in which in their lowest positions the guide members rest on the weight structure.

9. A structure according to claim 2 including an overhead frame supported on the weight structure and connected to the fender by a parallel linkage such that the fender will move horizontally and the overhead frame will rise and fall with the weight structure.

10. A structure according to claim 9 in which the adjustment means includes means for raising and lowering the guide members, said means being mounted on the overhead frame. 

1. A mooring structure comprising a fixed element, a rotatable head mounted on the fixed element and having first and second parts rotatable relative to one another from a rest position about a vertical axis, a weight structure supported by a plurality of pairs of ropes, the ropes of each pair being respectively connected to the first and second parts so that relative rotation of the parts from the rest position lifts the weight structure by increasing the angle between the ropes of each pair to provide an increasing restoring force tending to move the parts back to the rest position, a fender coupled to the mooring structure such that movement of the fender at least towards the mooring structure causes relative rotation of the head parts and adjustment means for adjusting the effective lengths of the pairs of ropes, whereby the restoring force per angular movement of the head parts is adjusted.
 2. A mooring structure according to claim 1 in which the adjustment means includes guide members, one associated with each pair of ropes and each arranged to maintain the ropes of its pair in a substantially common radial plane at and below the level of the guide members.
 3. A structure according to claim 1 in which the adjustment means includes guide members in the form of axle boxes, one associated with each pair of ropes, each axle box having a pair of pulleys engaging respective ones of its pair of ropes.
 4. A structure according to claim 3 in which for each axle box the edges of the pulleys engaged by the ropes lie in a substantially common radial plane.
 5. A structure according to claim 2 in which the ropes of each pair are anchored at their lower ends to the weight structure in a substantially common radial plane and pass through guide members before having their upper ends respectively connected to the first and second head parts.
 6. A structure according to claim 2 in which the adjustment means includes means for raising the guide members.
 7. A structure according to claim 6 in which the means for raising the guide members includes a support line for each guide member, all the support lines being connected to a drum and means for rotating the drum to wind up the support lines.
 8. A structure according to claim 2 in which in their lowest positions the guide members rest on the weight structure.
 9. A structure according to claim 2 including an overhead frame supported on the weight strUcture and connected to the fender by a parallel linkage such that the fender will move horizontally and the overhead frame will rise and fall with the weight structure.
 10. A structure according to claim 9 in which the adjustment means includes means for raising and lowering the guide members, said means being mounted on the overhead frame. 